Highly sensitivity sensors using thin planar dielectric gratings on flat metallic substrate

In this study, we propose surface plasmon resonance (SPR) sensors consisting of thin planar dielectric gratings on flat metallic substrate, which are studied by rigorous coupled-wave analysis theory (RCWA). The grating thickness is the most important factor to determinate the spectra shape and to influence the sensing performance. The results in air suggest the proposed sensor present extremely linear sensing characteristics with great sensitivity about 80 degree per refractive index unit and high FOM of 140.